This invention relates to certain pyridinyloxy-(pyrimidinyloxy)benzene derivatives which exhibit pre-emergence and post-emergence control of grasses and broadleaf weeds with safety to crops such as corn. More particularly, this invention relates to compounds such as 5-chloro-2-[2-(5-chloropyridin-2-yloxy)-phenoxy]pyrimidine and to a process for their preparation.
Australian Pat. No. 005412 (European patent application No. 79301533.0) to ICI Australia Ltd. discloses the following bis(pyrimidyloxy)benzene derivatives as pre-emergent and post-emergent herbicides. ##STR1## wherein A, B, D and E are H, halogen, NO.sub.2, CN, CNS, HCO, SO.sub.3 H, alkoxysulphonyl, YR, COYR, alkyl, alkenyl, cycloalkyl, alkylcarbonyl, NH.sub.2, Ph, carbamoyl or sulphamoyl;
Y is O or S; PA0 R is H, cation of inorganic or organic base; PA0 R.sub.1 -R.sub.6 are H, halogen, OH, NO.sub.2, CN, CNS, CO.sub.2 H, alkoxycarbonyl, alknyloxy, alkylthio, cycloalkyl, NH.sub.2, Ph, carbamoyl or sulphonyl; and PA0 W is O or S. PA0 2,2'-[1,2-phenylenebis(oxy)]bis[5-chloropyridine]; PA0 5-bromo-2-[2-(5-chloropyridin-2-yloxy)phenoxy]pyrimidine; PA0 5-chloro-2-[2-(5-nitropyridin-2-yloxy)phenoxy]pyridine; PA0 5-chloro-2-[2-(5-chloropyridin-2-yloxy)phenoxy]pyrimidine; and PA0 5-chloro-2-[2-(5-nitropyridin-2-yloxy)phenoxy]pyrimidine.
Compounds represented by the following structure are included in the Australian Patent. ##STR2## where X=Br or Cl.
United Kingdom application No. 7843037 to Ciba-Geigy discloses and claims a process for preparing hydroxydiarylethers which can be used as intermediates for preparing (phenoxy-phenoxy)alkanecarboxylic acids which have herbicidal and plant growth regulating action. The process comprises reacting a diether in a polar aprotic solvent in the presence of 0.1 to 1 mole of alkali per mole of diether to give a hydroxybenzene according to the following equation: ##STR3## wherein
R is an alkyl group of 1-4 carbon atoms or Cl;
X is a phenyl group of the structure ##STR4##
or a 2-pyridinyl group or a 4-pyridinyl group of the structure ##STR5## where R.sub.1 -R.sub.6 are H, alkyl, Ph, halogen, CF.sub.3, NO.sub.2 or CN.
European patent application No. 78300378.3 assigned to ICI Australia Limited (priority Sept. 13, 1977, AU 162677) discloses 2-phenoxy and 2-phenylthio pyrimidines and their use as pesticides. ##STR6##
A, B and D are H, halogen, hydroxy, nitro, cyano, thiocyano, optionally substituted alkyl, alkenyl, alkoxy, alkenyloxy, alkylthio, cycloalkyl, amino, phenyl, carboxy, alkoxycarbonyl, carbamoyl, sulfo, alkylsulfonyl or sulfamoyl;
R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are H, halogen, nitro, cyano, thiocyano, formyl, optionally substituted alkyl, alkenyl, cycloalkyl, alkylcarbonyl, amino, phenyl, carbamoyl, sulfo, alkoxysulfonyl or sulfamoyl; and
X is O or S.